Window and door shutters are conventionally made with a rectangular framework. Shutter blades are mounted transversely between the uprights of the framework. Some form of mechanism, sometimes a simple exterior rod, and in more complex cases, internal connections, interconnect the shutter blades so that when one blade is moved all of them move in unison between open and closed positions.
Such shutters provide an attractive interior appearance, and are regarded as an enhancement to interior decor. There are however two disadvantages. In the first place, the shutter doors are mounted on hinges, so that they can be swung away to expose the window or doorway around which they are fastened. When swung away, they occupy a certain amount of space within the interior of the room. In addition however, the cost of such shutter doors is relatively high. Consequently, the sales of such shutter doors are somewhat limited.
In the past, in an attempt to provide a compromise between shutter doors and venetian blinds a form of wooden blind has been manufactured using a header rail and ladder tapes, as in a venetian blind, but with the blind slats made of wood. However, these wooden venetian blinds have a somewhat limited market and their appearance does not always enhance the decor of the room. In addition however, such wooden venetian blinds could, generally speaking, be manufactured only in relatively restricted lengths. Ladder tapes were required at relatively frequent intervals to prevent the wooden shutter slats from sagging. Consequently, in situations where a relatively great continuous length of shutter was required, it was virtually impossible to use such wooden venetian blinds.
These wooden blinds are relatively unpopular due to their poor appearance, and lack of adaptability to wider spans. In addition, the use of such wooden slats is relatively expensive, since the wood must be of a relatively high quality, and must be free of warping. In addition, holes will be required to be formed through the wooden slats at intervals to receive the raise cords. This is a relatively slow and expensive machining operation and adds to the cost of such blinds.
An additional problem arises from the use of wooden blind slats supported by ladder tapes. Such wooden slats are relatively wide, being anywhere from two inches or more in most cases.
The ladder supports or "rungs" on the tapes must therefore be of a length equal to the width of the slats when in their "open" position i.e. horizontal. When the slats are in their closed position, the tapes themselves on either side of the slats are relatively closer together due to the weight of the slats, which causes each of the transverse ladder supports to sag downwardly in a loop drawing the two tapes together. However, when the tilt mechanism in the headrail is operated to move the ladder tapes so that the slats are rotated into their open positions, the slats will force the tapes relatively further and further apart. Bearing in mind that the slats are themselves of considerable weight, and there may be a large number of them in a single blind, it will be apparent that there will be considerable resistance encountered to the rotation of the slats from their closed to their open position. Consequently, the operation of the blind will appear to be stiff and awkward.
For all of these reasons, it is desirable to manufacture a suspended shutter having an improved appearance to more closely simulate the appearance of a shutter door having a frame. In addition, it is desirable to manufacture such a suspended shutter in an economical manner. It is also clearly desirable to manufacture such a suspended shutter which may be assembled to extend across a relatively wide span. It is further desirable to manufacture such a suspended shutter in which the rotation of the blades from closed to open position takes place smoothly with virtually no resistance due to spreading of the tapes.